Journal of Applied Physiology, Vol 47, Issue 6 1223-1227, Copyright © 1979 by American Physiological Society
Maximal work capacity of women during acute hypoxia
J. A. Wagner, D. S. Miles, S. M. Horvath and J. A. Reyburn
Six healthy women (22--34 yr of age) performed maximal bicycle work in a
hypobaric chamber at sea level and at simulated altitudes of 2,130 and
3,050 m (barometric pressures, 758, 586, and 523 Torr). Maximal oxygen
uptake (VO2max) decreased 10 and 15% from sea-level values at 2,130 and
3,050 m, respectively. At these altitudes minute ventilation (VEBTPS)
increased 17 and 22% respectively, a consequence of increased respiratory
rate (fR). Respiratory exchange ratios increased 10 and 14%, and oxygen
pulse decreased 9 and 12%, respectively, at 2,130 and 3,050 m. Maximal
blood lactates, heart rates, cardiac outputs, and plasma volume shifts were
unaffected by these altitudes. Although during maximal work the percentage
increases in VEBTPS, fR, and R that resulted from altitude exposure were
greater in women than those previously reported for men, the decrements in
VO2max were comparable to those in men. The results show that relative to
their performance at sea level, men and women have equal ability to perform
maximal work at altitudes up to 3,050 m.
